Catheter having insertion control mechanism

ABSTRACT

The present invention is a catheter having a tube and including mechanisms that provide precision control over insertion and retraction of the catheter tube. The catheter is particularly adapted for introduction into the pulmonary system. The catheter includes an insertion depth control mechanism that acts as a stop and provides a tactile indication to the person inserting the catheter tube that a predetermined position has been reached. The catheter also includes an anti-bunching mechanism to prevent bunching of a protective sleeve disposed around the catheter tube, thereby reducing interference from the sleeve during insertion of the catheter tube.

PRIORITY CLAIM

This application is a continuation of and claims the benefit of U.S.patent application Ser. No. 09/610,644, filed Jun. 12, 2000 now U.S.Pat. No. 6,702,789, which is a continuation of U.S. patent applicationSer. No. 09/038,465, filed Mar. 11, 1998 now abandoned, which claimspriority to provisional U.S. Patent Application Ser. No. 60/040,678,filed Mar. 11, 1997.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is related to the following commonly-owned co-pendingpatent application: “SLEEVED CATHETER HAVING INSERTION CONTROLMECHANISM”, U.S. application Ser. No. 10/768,852, filed Jan. 30, 2004.

TECHNICAL FIELD

The present invention relates to medical catheters, and moreparticularly to catheters used to remove substances from, or introducesubstances into, the pulmonary system or gastrointestinal tract of apatient.

BACKGROUND OF THE INVENTION

In certain medical treatment situations, catheters must be preciselyintroduced into a patient's pulmonary system or gastrointestinal tractfor various functions. For example, a patient may require involuntaryaspiration of secretions from the patient's lungs. In this situation, asuction catheter can be introduced into the patient's airway and lungsto remove the secretions via suction through the catheter. In addition,a patient may require introduction of various substances into the bodythrough such catheters. For example, a patient may require theintroduction of a lavage solution into the lungs to loosen secretionswithout interfering with ventilation.

Respiratory distress frequently occurs in infants and small children,especially prematurely born infants. Premature infants may requirerepeated pulmonary intervention. When an infant-or small child is unableto effectively breathe on their own, intubation and involuntaryventilation is provided via an endotracheal tube. In caring for infantpatients, it is necessary to periodically suction out secretions thatwould otherwise accumulate in the infant's lungs. This requires periodicinvoluntary removal of secretions from the lungs via a small suctioncatheter tube without injury to the lungs. Suctioning and/orintroduction of therapeutic substances may take place intermittentlyduring ventilation.

Suctioning is generally accomplished by introducing and advancing oneend of a flexible suction catheter tube into the endotracheal tube andapplying suction to the other end of the catheter tube. To reduce theextent of airway occlusion, the catheter tube is typically withdrawnfrom the endotracheal tube when the catheter is not in use.

Before the catheter tube is advanced through the endotracheal tube, thecatheter tube may be “exposed” within the catheter assembly. However,many catheters include a flexible sleeve that covers the span of tubingbetween the fittings of a catheter to avoid the introduction ofmicrobial pathogens during intubation. The sleeve encloses the cathetertube and preserves the sterility of the tube in a closed system. Thesleeve remains fixed to the fittings of the catheter. The sleeve isflexible so that the catheter can be advanced by manipulating thecatheter from the outside of the sleeve. Thus, the catheter may beintermittently introduced without breaking the sterile field created bythe sleeve around the catheter.

Precise control over the placement of the catheter tube is also requiredto reduce the risk of injury during placement. The catheter must beadvanced far enough to effectively reach the lungs without damagingtissue by overextension of the catheter. The use of a catheter having aprotective sleeve further impacts control over the catheter duringplacement. As the catheter is fully advanced, the sleeve may bunch,making precise control more difficult. Thus, there is a need for acatheter having a mechanism for controlling insertion depth whilepreventing bunching of the protective sleeve as the catheter isinserted.

SUMMARY OF THE INVENTION

The present invention is a catheter having a tube and includingmechanisms that provide precision control over insertion and retractionof the catheter tube. The catheter is particularly adapted forintroduction into the pulmonary system. The catheter includes aninsertion depth control mechanism that acts as a stop and provides atactile indication to the person inserting the catheter tube that apredetermined position has been reached. The catheter also includes ananti-bunching mechanism to prevent bunching of a protective sleevedisposed around the catheter tube, thereby reducing interference fromthe sleeve during insertion of the catheter tube.

In one embodiment, the insertion depth control mechanism comprises aninsertion control member that is adjustably positioned on the cathetertube. The insertion control member includes a releasable catch to permitadjustment of its position along the catheter tube. When placed in apredetermined position that corresponds to a predetermined insertiondepth, the insertion control member acts as a stop against a connectoror other form attached to the tube. When the insertion control memberreaches the connector or form during insertion of the tube, it bumpsagainst the connector or form and stops the advancement of the cathetertube at a predetermined length. This resistance provides a tactileresponse, or feel, to a person inserting the catheter, which indicatesthat the catheter tube has been inserted to the predetermined depth. Theinsertion control member can comprise a number of different shapes.

In one embodiment, the anti-bunching mechanism comprises a sleevespreader including an outer surface concentrically disposed around thecatheter tube and adjacent a tube opening of a distal connector attachedto the catheter. The sleeve spreader deflects the sleeve away from thetube opening of the distal connector and prevents it from bunching atthe tube opening, thereby avoiding interference with advancement of thecatheter tube.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a catheter of the present inventionincluding a connector for a ventilation apparatus.

FIG. 2A is a perspective view of a first embodiment of an insertioncontrol member of the present invention.

FIG. 2B is a cross-sectional view of the insertion control member shownin FIG. 2A taken transversely through the center of the insertioncontrol member.

FIG. 3 is a cross-sectional side view of a second embodiment of aninsertion control member of the present invention.

FIG. 4 is a cross-sectional view of a sleeve spreader of the cathetershown in FIG. 1.

FIG. 5A is an elevational view of a second embodiment of a sleevespreader of the present invention.

FIG. 5B is a cross-sectional view of the sleeve spreader shown in FIG.5A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the present invention will be described fully hereinafter withreference to the accompanying drawings, in which a particular embodimentis shown, it is to be understood at the outset that persons skilled inthe art may modify the invention herein described while still achievingthe desired result of this invention. Accordingly, the description whichfollows is to be understood as a broad informative disclosure directedto persons skilled in the appropriate arts and not as limitations of thepresent invention.

FIG. 1 is an exploded view of a suction catheter 20 and associatedattachments for use in a typical ventilator circuit. The suctioncatheter 20 incorporates an insertion depth control mechanism and ananti-bunching mechanism as described herein. The suction catheter 20includes a catheter tube 21, a proximal end 22 having a proximalconnector assembly 24, and a distal end 26 having a distal spreaderconnector 28. The proximal connector assembly 24 includes a sleevecollar 30, a vacuum valve 32, and a terminal connector 34. The distalspreader connector 28 includes a sleeve collar 35 and a generallycone-shaped extension 36 that extends toward the proximal end 22 of thecatheter 20. The cone-shaped extension includes a tube aperture 37. Thecatheter tube 21 passes through the tube aperture 37. The distalspreader connector 28 has a fitting 38 that can be connected to anadapter device 39. To complete the ventilation circuit, the adapterdevice 39 is connected to a conventional ventilation adapter 40 thatincludes an endotracheal tube 42 having an end opening 44. Othercomponents may be used in connection with the suction catheter 20without departing from the present invention, such as those disclosed inU.S. Pat. No. 5,642,726, which is incorporated herein by reference.

The catheter tube 21 of the suction catheter 20 is surrounded by aflexible external sleeve 46 that spans from the proximal connectorassembly 24 to the distal spreader connector 28, as shown in FIG. 1. Theexternal sleeve 46 is attached to the proximal connector assembly 24within the sleeve collar 30 and the distal spreader connector 28 withinthe sleeve collar 35. The sleeve 46 may be banded to the sleeve collars30 and 35 or adhered thereto. The external sleeve 46 encloses thecatheter tube 21 to preserve its sterility during use in a closedsystem.

During intubation, the catheter tube 21 of the suction catheter 20 isintroduced into the endotracheal tube 42 through the distal spreaderconnector 28 and the adapter device 39 and advanced to a predetermineddepth. The depth of insertion is controlled by an insertion controlmember 50. During insertion of the catheter tube 21, the insertioncontrol member 50 acts as a stop against the cone-shaped extension 36 ofthe distal spreader connector 28, thus stopping the advancement of thecatheter at a predetermined length. The insertion control member 50 alsoprovides a tactile feel to the operator when it bumps against theextension 36, thereby signaling to the operator that the proper depthhas been reached.

In the embodiment depicted in FIG. 1, the insertion control member 50has a generally barreled shape as shown in FIGS. 2A and 2B. Theinsertion control member 50 includes two flattened grip portions 52 anda tube passage 54. As shown in FIG. 2B, the tube passage 54 has anelongated cross-section near the center of the insertion control member50. The catheter tube 21 passes through the tube passage 54 and theelongated configuration of the tube passage 54 grips the catheter tube21 to hold the insertion control member 50 at a predetermined positionalong the catheter tube 21. The catheter tube 21 may include indicia tohelp facilitate depth adjustment of the catheter tube 21 via theinsertion control member 50. The position of the insertion controlmember 50 can be adjusted by an operator pinching the insertion controlmember 50 at the flattened grip portions 52 to flex the elongatedcross-section of the of the tube passage 54 to form a relatively widercross-section. The wider cross-section allows the operator to slide theinsertion control member 50 to a new position on the catheter tube 21.When the insertion control member 50 is repositioned, the operatorreleases the flattened grip portions 52 so that the cross-section of thetube passage 54 returns to its elongated configuration. Alternatively,the cross-section of the tube passage 54 may include other features tohelp grip the catheter tube 21, such as teeth or other projections.

FIG. 3 shows an alternate embodiment in the form of an insertion controlassembly 60. The insertion control assembly 60 includes a threadedsleeve 62 having a thru-hole 64 and external threads 66 on one end ofthe sleeve 62. The thru-hole 64 has a tapered surface 68 that accepts atapered collet 70, as shown in FIG. 3. The tapered collet 70 includes achannel 72 therethrough. A mating nut 74 includes a thru-hole 76 andinternal threads 78 that are adapted to engage the external threads 66of the threaded sleeve 62. The catheter tube 21 passes through thethru-hole 64 of the threaded sleeve 62, the channel 72 of the taperedcollet 70, and the thru-hole 76 of the mating nut 74. When the threadedsleeve 62 and the mating nut 74 are engaged and tightened, the threadedsleeve 62 deflects and compresses the tapered collet 70 around thecatheter tube 21, thereby securing the insertion control assembly 60 tothe catheter tube 21.

FIG. 4 is a cross-sectional view of the distal spreader connector 28shown in FIG. 1. As the catheter tube 21 is advanced through the distalspreader connector 28 and the adapter device 38, the external sleeve 46begins to bunch up near the distal spreader connector 28. Thecone-shaped extension 36 of the distal spreader connector 28 acts tospread or deflect the sleeve 46 as the catheter tube 21 is advanced andprevent the sleeve 46 from interfering with the tube opening or aperture37 of the extension 36 of the distal spreader connector 28. The sleeve46 is attached to the distal spreader connector 28 between the collar 35and the extension 36, as shown in FIG. 4.

FIGS. 5A and 5B show an alternate embodiment in the form of a distalspreader connector 80. In this embodiment, the distal spreader connector80 includes a set of four tapered ribs 82 that extend from an extension84. The tapered ribs 82 provide further deflection and spreading of thesleeve 46 as the catheter tube 21 is advanced. Accordingly, the distalspreader connector 80 deflects the sleeve adjacent to the tube openingof the distal spreader connector.

While the specific embodiments have been illustrated and described,numerous modifications come to mind without significantly departing fromthe spirit of the invention and the scope of protection is only limitedby the scope of the accompanying claims.

1. A catheter comprising: a tube having: (a) a first end; (b) a firstconnector connected to the first end, the first connector beingconfigured to be coupled to a medical device; (c) a second end; (d) anintermediate portion between the first end and the second end; and (e) asecond connector connected to the second end, the second connector beingconfigured to be in fluid communication with an anatomical passageway ofa patient, the second end being movable through the second connector ina direction toward or away from the patient so that the intermediateportion of the tube is disposed along an axis between the firstconnector and the second connector; and a controller carried on theintermediate portion of the tube, the controller being movable along theaxis between: (x) at least one position in which the controller is incontact with the second connector; and (y) at least one other positionin which the controller is apart from the second connector, thecontroller having: (i) a tube engagement member defining a predisposednon-circular shape, and (ii) a depressible portion, depression of thedepressible portion operable to cause the tube engagement member tobecome more circular than the non-circular shape to facilitate movingthe controller along the axis.
 2. The catheter of claim 1, wherein thetube has a diameter.
 3. The catheter of claim 2, wherein the depressibleportion of the controller includes a flexible wall having an outersurface and an inner surface, the inner surface defining a tubepassageway having a plurality of variable diameters.
 4. The catheter ofclaim 3, wherein the flexible wall is flexible between: (a) apredisposed position wherein at least one of the variable diameters isless than the diameter of the tube; and (b) another position whereineach of the variable diameters is greater than the diameter of the tube.5. The catheter of claim 4, wherein the outer surface of the flexiblewall has a plurality of grip portions which assist a user in pinchingthe controller in order to reposition the controller on the tube.
 6. Thecatheter of claim 1, wherein the controller has a tactile indicatorwhich provides a signal to a user that the tube has been moved a certaindistance.
 7. The catheter of claim 1, wherein the second connector isconfigured to be operatively coupled to an endotracheal tube receivableby the patient.
 8. The catheter of claim 1, wherein the medical deviceincludes negative pressure produced by a suction apparatus.
 9. Thecatheter of claim 1, wherein the second connector is in fluidcommunication with a ventilation circuit.
 10. The catheter of claim 9,wherein the ventilation circuit includes positive pressure produced by aventilation device.
 11. A catheter comprising: a tube having: (a) afirst end; (b) a first connector connected to the first end, the firstconnector being configured to be coupled to a medical device; (c) asecond end; (d) an intermediate portion between the first end and thesecond end; and (e) a second connector connected to the second end, thesecond connector being configured to be in fluid communication with ananatomical passageway of a patient, the second end being movable throughthe second connector in a direction toward or away from the patient sothat the intermediate portion of the tube is disposed along an axisbetween the first connector and the second connector; indicia located onat least part of the intermediate portion of the tube; and a controllercarried on the intermediate portion of the tube, the controller beingmovable along the axis between a plurality of different positionsrelative to the second connector, the controller having a tubeengagement member defining a predisposed non-circular shape, depressionof the controller causing the predisposed non-circular shape to becomecloser to a circular shape to facilitate moving the controller along theintermediate portion.
 12. The catheter of claim 11, wherein the tube hasa diameter.
 13. The catheter of claim 12, wherein the controllerincludes a flexible wall having an outer surface and an inner surface,the inner surface defining a tube passageway having a plurality ofvariable diameters.
 14. The catheter of claim 13, wherein the flexiblewall is flexible between: (a) a predisposed position wherein at leastone of the variable diameters is less than the diameter of the tube; and(b) another position wherein each of the variable diameters is greaterthan the diameter of the tube.
 15. The catheter of claim 14, wherein theouter surface of the flexible wall has a plurality of grip portionswhich assist a user in pinching the controller in order to repositionthe controller on the tube.
 16. The catheter of claim 11, wherein thecontroller has a tactile indicator which provides a signal to a userthat the tube has been moved a certain distance.
 17. The catheter ofclaim 11, wherein the second connector is adapted to be operativelycoupled to an endotracheal tube receivable by the patient.
 18. Thecatheter of claim 11, wherein the medical device includes negativepressure produced by a suction apparatus.
 19. The catheter of claim 11,wherein the second connector is in fluid communication with aventilation circuit.
 20. The catheter of claim 19, wherein theventilation circuit includes positive pressure produced by a ventilationdevice.
 21. A catheter comprising: a tube having: (a) a diameter, (b) afirst end; (c) a first connector connected to the first end, the firstconnector being configured to be coupled to a medical device; (d) asecond end; and (e) a second connector connected to the second end, thesecond connector being configured to be in fluid communication with ananatomical passageway of a patient, the second end being movable throughthe second connector in a direction toward or away from the patient sothat a portion of the tube is disposed along an axis between the firstconnector and the second connector; indicia located on at least part ofthe portion of the tube; and a placement controller which is: (x)supported by the portion of the tube; and (y) disconnected from thesecond connector, the placement controller being adjustably positionedon the portion of the tube, the placement controller including aflexible wall having an outer surface and an inner surface, the innersurface defining a tube passageway having a plurality of variablediameters, the flexible wall being flexible between: (i) a predisposednon-circular shape wherein at least one of the variable diameters isless than the diameter of the tube; and (ii) another shape which is morecircular than the non-circular shape to facilitate moving the placementcontroller along the axis, the placement controller further including aplurality of substantially flattened grip portions positioned atopposite sides of the flexible wall.
 22. The catheter of claim 21,wherein the placement controller has a tactile indicator which providesa signal to a user that the tube has been moved a certain distance. 23.The catheter of claim 21, wherein the second connector is configured tobe operatively coupled to an endotracheal tube receivable by thepatient.
 24. The catheter of claim 21, wherein the medical deviceincludes negative pressure produced by a suction apparatus.
 25. Thecatheter of claim 21, wherein the second connector is in fluidcommunication with a ventilation circuit.
 26. The catheter of claim 21,wherein the ventilation circuit includes positive pressure produced by aventilation device.